1. Field of the Invention
The present invention relates to an aircraft simulation method and apparatus, and in particular, to an aircraft simulation method and apparatus using a transfer function modeling approach which saves CPU (central processing unit) processing power during a computer implemented simulation of an aircraft.
2. Description of the Related Art
Aircraft simulators are often used in the training of pilots, and typically include a simulation environment as shown in FIG. 1. The simulation environment is generally made up of a mock cockpit 100 having an instrument panel 101, sensor indicators 102, control devices (e.g., flight stick) 103, G-force simulators 104 and video displays 105 for visual simulations, all of which are under control of a CPU 106. To effect simulation, programs are needed to create an aircraft model that has similar performance and flight characteristics to a known existing aircraft. In most instances, the desired aircraft model is incorporated into the simulation environment model as a threat or wingman. Typically, the system operates according to a database of preprogrammed simulation scenarios which are selected by the pilot during a simulated mission.
The aircraft model should preferably require as little CPU processing as possible to allow a large number of the aircraft models to participate in the simulation environment. However, in most circumstances, the known existing aircraft is hosted as a full fidelity model. The full fidelity model calculates the complex set of forces and other variables acting on the aircraft and thus requires substantial processing power to implement. It is not possible to rehost the full-fidelity model as one of many aircraft in a simulation environment without placing severe restrictions on processing power. Nonetheless, most simulations simply incorporate the full fidelity model, and sacrifice the CPU processing power. Other simulation methods include the use of an existing "transfer function" dynamic model in which coefficients are adjusted manually until the aircraft response seems about right to the user.
In short, existing simulators suffer drawbacks in that substantial processing power is needed to implement the full fidelity model, and in that the alternative transfer function dynamic model relies on the manual and often subjective adjustment of the transfer function coefficients.